This invention relates to the production of aluminum phosphate gel.
Aluminum phosphate gel has long been known as a base for various catalysts including chromium olefin polymerization catalysts. However, it has never achieved commercial success because the results obtained therewith have not been sufficiently good to make it economically feasible. Recently new techniques have been developed to give an aluminum phosphate which is superior in certain respects to commercial silica supports for chromium olefin polymerization catalysts. Such new techniques are disclosed in McDaniel et al. U.S. Pat. No. 4,364,855 (Dec. 21, 1982), for instance. Aluminum phosphate does, however, suffer the disadvantage of producing fines (undesirably small catalyst particles) when the catalyst is subjected to normal handling operations. The fines present a dual problem in that they complicate the activation procedures and result in the production of polymer fines when the catalyst is used in polymerization. Fines produced during stirring at the hydrogel stage make more difficult subsequent filtering operations as well as remaining as fines in the final catalyst.